Definitions

merciless

[mur-si-lis] / ˈmɜr sɪ lɪs /

ADJECTIVE

mean, heartless

Synonyms

STRONGEST

barbarous callous cruel fierce grim harsh implacable inexorable inhumane relentless ruthless severe unforgiving unrelenting unsparing unyielding

STRONG

unmerciful

WEAK

compassionless cutthroat dog-eat-dog gratuitous hard hardhearted hatchet job having a killer instinct iron-fisted mean machine mortal pitiless unappeasable uncalled-for unfeeling unflinching unpitying unsympathetic wanton

Antonyms

STRONGEST

bright calm compassionate considerate easy feeling flexible gentle kind merciful mild nice peaceful polite remorseful sympathetic tender yielding

WEAK

giving sparing

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

He was exacting, charming and merciless in equal measure.

From BBC • Apr. 10, 2026

He had been in Britain since 208, overseeing a series of merciless campaigns into present-day Scotland.

From The Wall Street Journal • Mar. 19, 2026

The 1972 peak was followed by a merciless recession in the mid-1970s, and a heartbreaking stock market bust.

From Barron's • Dec. 31, 2025

In particular, Hawaii Supreme Court Justice Todd Eddins has emerged as one of the judiciary’s most astute and merciless critics of the Roberts court.

From Slate • Sep. 19, 2025

Holly looked the troll straight in its merciless eyes and pressed the button.

From "Artemis Fowl" by Eoin Colfer

Vocabulary lists containing merciless

Hamilton

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Schooled

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Theodore Roosevelt on "The Man with the Muck Rake" (1906)

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